734391 - coalesce the device motion events

Status: RESOLVED FIXED

(Core :: DOM: Geolocation, defect)

Description

[Doug Turner (:dougt)]

We can improve perf a bit by not sending 3 separate dom events.  Instead, we can coalesce the device motion events by waiting a bit to see if there is additional motion data before posting the dom event.

Comment 1

[Doug Turner (:dougt)]

Attachment: patch v.1

Comment 2

[Josh Matthews [:jdm]]

Comment on attachment 604421 [details] [diff] [review]
patch v.1

Review of attachment 604421 [details] [diff] [review]:
-----------------------------------------------------------------

r=me

::: dom/system/nsDeviceMotion.cpp
@@ +344,5 @@
>                                     double x,
>                                     double y,
>                                     double z) {
> +  // Attempt to coalesce events
> +  bool fireEvent = false;

Just assign the result of the condition to fireEvent?

@@ +345,5 @@
>                                     double y,
>                                     double z) {
> +  // Attempt to coalesce events
> +  bool fireEvent = false;
> +  if (PR_IntervalNow() > mLastDOMMotionEventTime + PR_MillisecondsToInterval(DEFAULT_SENSOR_POLL))

Let's use TimeStamp::Now() and TimeDuration::FromMilliseconds instead.

@@ +391,5 @@
> +
> +  mLastRotationRate = nsnull;
> +  mLastAccelerationIncluduingGravity = nsnull;
> +  mLastAcceleration = nsnull;
> +  mLastDOMMotionEventTime = PR_IntervalNow();

TimeStamp::Now()

::: dom/system/nsDeviceMotion.h
@@ +98,5 @@
>    virtual void Startup()  = 0;
>    virtual void Shutdown() = 0;
> +
> +  bool mEnabled;
> +  PRIntervalTime mLastDOMMotionEventTime;

TimeStamp

Comment 3

[Ed Morley [:emorley]]

Sorry, backed out for OS X M1/M3 oranges:
https://tbpl.mozilla.org/?tree=Mozilla-Inbound&rev=c619bbb2951f
https://tbpl.mozilla.org/php/getParsedLog.php?id=10039398&tree=Mozilla-Inbound
https://tbpl.mozilla.org/php/getParsedLog.php?id=10039239&tree=Mozilla-Inbound

https://hg.mozilla.org/integration/mozilla-inbound/rev/ec55dae77b79

Comment 4

[Matt Brubeck (:mbrubeck)]

Re-landed and merged:
https://hg.mozilla.org/mozilla-central/rev/ed1d52905a61